Oil Temp

[Ablight]

I need ideas on getting my oil temp up to 180 or so, right now I can't get hotter than 150 when the OAT is 30 degrees or less. I have the cover over the air scoop in the nose bowl and I have the wag-aero oil tank cover kit coming. I also have mufflers inside the cowling. 85hp with o200 STC, wood prop. Thanks...Andy

[pablo]

Andy: My Champ's A-65 oil temp never gets above 66C in the winter or above 88C in the summer (Oklahoma Weather). Never has been a problem. Pablo

[Nathan K. Hammond]

Andy,

Preheatting is a big key to good oil temp. I've used several different methods, from pads on the oil tank to light bulbs. The pads are nice but it took 6 hours to get a good preheat. Next was a little box heater with a peice of stove pipe stuck around it. This kept the heater outside the engine cowl and on the floor in case of a fire. I just squished the pipe together so it would fit into the opening at the bottom of the cowl. It was fairly successful, but I was alway afraid of a fire so I would end up spending an hour or 2 in the cold hangar keeping an eye on things. By far the best method I've used was a light bulb. Get one of the clamp-on shop lights and remove the shield, put in a 100 Watt bulb and position it under the Oil tank and in 2 hours (20 Degrees F. OAT) had oil at 80 degrees. And with the light bulb, I didn't have any problem with hooking it up and waitting in the FBO or Hardy's. With what ever I used, there was a sleeping bag draped over the cowling and clamped together on the bottom, to keep much heat in the engine compartment as possible.

Thats anouther good thing about the boxfan and light bulb....they tend to heat the entire engine, not just the sump as with a pad.

And don't get me wrong, the pads are probably the best way to do it, I just didn't want to drive out the the A/P the night before to hook it up.

After preheating, you will have to restrict the airflow over the engine. The easiest way is to simply get some tape (Duct, or wide 3" electrical) and put it over the inlet eye's. Be careful and think about what your doing, you can easily create hot spots on the front two cylinders. DO NOT put a couple vertical strips of tape on the outboard sides of the openings! You would be blocking coolling air to the hottest part of the engine, and in no time could cook the cylinders.

Run a piece or two of tape horizontally across the top of the eyellets, and see what the temp reads. If it needs more, run a peice across the bottom.

The tank cover is a good idea. Keep in mind that it only helps to hold what ever heat is built up. I had one and also the intake tube covers for a couple years, and too be honest, I couldn't tell a difference with them on or off. The oil tank cover finally became oil soaked, so I simply threw it away. For as little as it gave back, I would have felt pretty damn stupid and mad if it caught fire.

Hope this helps.

nkh

[MikeB]

Getting the temperature up in cold weather always seems to be a problem with the Champs (don't know about Chiefs). Mine will usually run 170 or so in the summer and lucky to see 160 in the winter. Usually about 150F depending on the outside temperature (ambient). In my humble opinion, part of the problem getting the temperature up can probably be related to the engine not using a lot of fuel (4-5 GPH) therefore not a lot of heat is being generated. Also, the engine is pretty open cowled, but so are a lot of other engines for that matter. Closing off the "engine block opening" helps some. I've never tried it, but I've read that closing off the lower cowl (outlet) helps (like cowl flaps). Always been afraid to try it as I wouldn't want to cook a cylinder and don't have a cylinder temperature gauge. I've seen some other planes with restriction baffles with holes in them over the inlet "eye". Here again, how do you know how well you are cooling the cylinders (or should I say, not cooking them). Mufflers help some. At least they generate enough heat so something other than your left toe is warm. My Champ with mufflers is pretty warm, even with 150F oil temperature.

With a winterization plate over the oil cooler, my Cherokee 140 will run 180 degrees.

On the bright side, at least the cold oil temperature holds the oil pressure up. I usually see 28 # at 170F and 32# at 150F with 20W50 oil.

[ablight]

Thanks to all for the insight. I do preheat, I have a propane fired electic heater that works great. My worry is the moisture in the oil, boiling it off. The engine is new and I would hate to have to replace it in a few years because of corrosion. Covering the eyelets scares me, like the previous post I worry about hot spots on those new millenium cylinders $$$. I'm at a loss? What about an oil additive like Avblend? This engine has 16 hours TT since overhaul. When should you use an additive? Thanks Andy

[Jim Catalano]

Hi Andy!
150 degrees!! Heck, I'm happy if the needle moves off the peg. The scrotum and intake covers are next to useless and a pain to put on and off. Worry less/ fly more...Jim

[mike berg]

I'm not a big fan of oil additives. I guess my reasoning is that if it needed to be in there, the oil manufacturer would have put it in there. A good grade of aviation oil, either a straight weight proper for the season, or a multi-weight (my preference) changed on a regular basis is all that is required. I'm basing this on having spent the last 40 some years of my life associated with the trucking business. There was always someone around to sell "snake oil" but I never could see the value of any over the long run. Most of them don't hurt anything, but are not much help either, in my humble opinion.

With a new set of cylinders ($$$$) you are right to be concerned about keeping the engine temperature up not only to prevent the accumulation of moisture in the crankcase, but more importantly, to keep the cylinders from being glazed. We majored one of the Champs on our field with new cylinders last winter, but elected to wait until spring to install it for that very reason.....so far, so good. However, I'd think that with 16 hours on the engine and 150 degree temperature you should be ok, assuming you don't "baby" the engine and avoid long, low power descents.

My two cents worth.

[LOWELL]

I haven't found an answer yet. My A-65 runs approx. 150 F in the winter
but I change the oil in the Fall (15w50) when it gets cold then again around
March. I've found oil is real cheep compaired to eng. parts. You might
want to drain the oil and heat it to 170/180 to get the moisture out. Use
a hot plate, not an open flame. I perfer just to change the oil, it is safer.
A good way to check your oil temp is to get a can of water, pull the temp
probe from the oil screen, place in the water (don't let it touch the sides)
use a propane torch to heat to a boil, check oil temp to see what it reads,
about 212F at sea level. There is a chart in your wifes/girl friends cook book that will give you boiling temps at different elevations.
Best of luck,
Lowell

[Jim Catalano]

I agree with Mike and Lowell, skip the additives and change the oil often.
There is an ad in Sport Aviation for the "Engine Saver"@ www.flyingsafer.com.???? Jim

[Ron Babos]

Had a temp guage in my Champ, much like Jims, as it would only go to 120 on the first few flights. Changed the Scott guage and temp went to 160. This is still too cold, so I now fly with the opening blocked under the prop. On a hot day it will hit 185. Any less than 170-180 you've got a big condenser working for you. The down side is that if your engine is baffed, your idle pressure will be very low, and cruise pressure will drop a few pounds also. Contrary to what you may think, colder oil is not better, even though you see a higher pressure. 170-190 with a good tight engine with normal pressure is the best situation to have. It will last longer due to lack of moisture and better lubrication. Remember cylinders and pistons are lubed from splashed oil. Ron

[MikeB]

Hope I wasn't giving the impression that I thought cold oil was good for the engine (just to keep the pressure up). I was just relating to the fact that my **&&%%$#- (AP/AI) rebuilt engine has suffered from what I consider to be lower than "normal" oil pressure since I've installed it. I'm sure the problem lies in the condition of the oil pump and accessory case cover. It runs on the low side of what I consider to be "normal" at around 170 F, but has ran like that for over 100 hours, with no problems and no metal. One of these days, I'm going to pull the back cover, but it is nice to see more than 30# pressure once in a while.
Even at 150 degrees, I'm sure there's plenty of oil spashing around.
(When I called the guy who rebuilt the engine, he suggested I run 50 weight oil.............yeah, right!!).

[Ron Babos]

Yup: I know what you mean. Just got a supposedly mint case from an engine builder. The cam bore at the front had.010 clearance. A good bearing for gear oil. The one cylinder had a .009 slant. Did all the machine work myself, as it seem you can't trust the pros to do it right. The worst part is, this case would have been built up into an engine and sold to some poor sap for a premium dollar. When questioning the cam bore clearance, he said it's not all that important. In my experience, it's the most important hole in the case, if you want oil pressure. The learning curve is very expensive in aviation, as most of us have found out. Ron

[LOWELL]

If you have not tried this with low oil press., pull the press relf. assy.
and see if there is any washers between the spring and cap. If not. add
one washer at a time (max. of three) and see if the oil press will stay
up when the oil gets hot. If not, bad oil pump, bearings warn could be the
problem. I use a AN960-416 washer, (1/4" washer)
Best of luck,
Lowell

[smokiescfi]

Does anyone know of a source for the cover that is meant to fit over the oval hole between the aircleaner and the prop???

[Nathan K. Hammond]

Safe Air Repair is bound to have them, or Buzz Wagner......hmmm . It's a fairly simple device to make if your incline too. Just cut a peice of Alum. to fit, then take a couple old inspection plates and drill off the springs on the back. Either screw or rivit the springs on the cover. You'll have about a buck in it if your a good scrounger.

nkh